int sumarray3d(int a[N][N][N])
{
 int i,j,k,sum=0;
 for (i=0;i<N;i++)
 {
  for (j=0;j<N;j++)
   {
    for(k=0;k<N;k++)
     {
      sum+=a[k][i][j];
     }
   }
 }
 return sum;
}

